It is common in motor vehicles to construct a vehicle frame or vehicle body by forming or assembling various panels into a hollow tubular structure, or a channel structure. It is necessary to bolt such a hollow frame member to additional structure of the vehicle. It is desirable in some manner to mount a nut inside the hollow tubular member, overlying a hole through the tubular member, so that a bolt may subsequently be threaded into the nut to make the attachment to the hollow frame member. It is well known in such applications to simply weld the nut inside the tubular member, preferably before the tubular member is assembled. Furthermore it is well known to mount the nut within a cage so that the nut is captured in a loose fitting manner by which the nut may be moved somewhat in relation to the hole through the tubular member to properly align with the attaching bolt.
Frequently, such hollow frame members are constructed by welding together the edges of a pair of U-shaped channels. Accordingly, the weld nut or the cage nut may be welded to one of the channels before the channels are welded together to form the hollow frame member. After the channel members are welded together, the hollow frame member is painted and the application of paint fouls the threads of the nut.
It would be desirable to provide a nut which could be installed inside a hollow frame member subsequent to the assembly of the hollow frame member and the painting of the frame member.